{
  "$defs": {
    "RequiredParent": {
      "properties": {
        "value": {
          "title": "Value",
          "type": "integer"
        }
      },
      "required": [
        "value"
      ],
      "title": "RequiredParent",
      "type": "object",
      "x-is-base-class": true
    }
  },
  "allOf": [
    {
      "$ref": "#/$defs/RequiredParent"
    }
  ],
  "properties": {
    "value": {
      "default": 2,
      "title": "Value",
      "type": "integer"
    }
  },
  "title": "OptionalChild",
  "type": "object"
}